1. What is the Physical Activity Coefficient?

The Physical Activity Coefficient (PA) is a dimensionless number that represents the ratio of energy expended during physical activity to the total daily energy expenditure. It's used in various health and fitness calculations to quantify activity levels.

2. How Does the Calculator Work?

The calculator uses the Physical Activity equation:

Where:

• \( MET \) — Metabolic equivalent of task (activity intensity)
• \( time \) — Duration of activity in hours
• 24 — Total hours in a day

Explanation: The equation calculates what portion of a day's energy expenditure comes from a specific activity by multiplying the activity's MET value by its duration and dividing by 24 hours.

3. Importance of PA Calculation

Details: The PA coefficient is important for estimating total daily energy expenditure, designing exercise programs, and assessing physical activity levels in research studies.

4. Using the Calculator

Tips: Enter the MET value of your activity (common values range from 1.0 for sitting to 8.0+ for vigorous exercise) and the duration in hours. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What are typical MET values for common activities?
A: Sleeping: 0.9, Sitting: 1.0, Walking (3mph): 3.0, Running (6mph): 10.0, Swimming: 5-10 depending on intensity.

Q2: How is PA different from PAL (Physical Activity Level)?
A: PA is activity-specific while PAL is a ratio of total daily energy expenditure to basal metabolic rate.

Q3: Can I add multiple activities?
A: For multiple activities, calculate each separately and sum the PA values, ensuring the total time doesn't exceed 24 hours.

Q4: What's a good PA value?
A: Values vary by individual goals. Sedentary lifestyles might have PA < 0.5, while active individuals may have PA > 1.0.

Q5: How accurate is this calculation?
A: It provides an estimate. Actual energy expenditure depends on factors like body composition, fitness level, and exercise efficiency.